Health Consultation Residential Vapor Intrusion Investigation
FORMER HARDESTY FEDERAL COMPLEX
KANSAS CITY, MISSOURI
Prepared by
Missouri Department of Health and Senior Services
JULY 11, 2016
Prepared under a C ooperative A greement with the
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Agency for Toxic S ubstances and Disease Registry
Division of Community Health Investigations
Atlanta, Georgia 30333
Health Consultation: A Note of Explanation
A health consultation is a verbal or written response from ATSDR or ATSDR’s
Cooperative Agreement Partners to a specific request for information about health risks
related to a specific site, a chemical release, or the presence of hazardous material. In order
to prevent or mitigate exposures, a consultation may lead to specific actions, such as
restricting use of or replacing water supplies; intensifying environmental sampling;
restricting site access; or removing the contaminated material.
In addition, consultations may recommend additional public health actions, such as
conducting health surveillance activities to evaluate exposure or trends in adverse health
outcomes; conducting biological indicators of exposure studies to assess exposure; and
providing health education for health care providers and community members. This
concludes the health consultation process for this site, unless additional information is
obtained by ATSDR or ATSDR’s Cooperative Agreement Partner which, in the Agency’s
opinion, indicates a need to revise or append the conclusions previously issued.
You May Contact ATSDR Toll Free at
1-800-CDC-INFO
or
Visit our Home Page at: http://www.atsdr.cdc.gov
http:http://www.atsdr.cdc.gov
HEALTH CONSULTATION
Residential Vapor Intrusion Investigation
FORMER HARDESTY FEDERAL COMPLEX
KANSAS CITY, MISSOURI
Prepared By:
Missouri Department of Health and Senior Services
Division of Community and Public Health
Section for Environmental Public Health
Bureau of Environmental Epidemiology
Under a Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry
SUMMARY
Introduction The Missouri Department of Health and Senior Services
(MDHSS), in cooperation with the federal Agency for Toxic
Substances and Disease Registry (ATSDR), has developed this
health consultation to evaluate the potential health impacts of
exposure to volatile organic compounds (VOCs) in indoor air at
residences and other occupied buildings near the former Hardesty Federal Complex site in Kansas City, Missouri (MO).
The detection of trichloroethylene (TCE) and other chlorinated
VOCs in groundwater at the former Hardesty Federal Complex has prompted concerns that individuals in the surrounding
neighborhood may be breathing those VOCs, which may volatilize
from groundwater, migrate into buildings, and accumulate in
indoor air to levels of potential health concern as a result of vapor
intrusion. In August-October 2014, the United States General
Services Administration (GSA) in coordination with the Missouri
Department of Natural Resources (MDNR) conducted initial vapor
intrusion (VI) sampling at two homes thought to be in the path of
the groundwater contamination. In this health consultation,
MDHSS has reviewed the results of that limited investigation and
has made recommendations for an expanded VI investigation.
Conclusions MDHSS has reached two important conclusions:
Conclusion 1 In the past, breathing TCE in indoor air may have posed increased
health risks in two residences northeast of the former Hardesty Federal Complex site. Of particular concern are the increased risks of fetal heart malformations from TCE exposure during the
weeks in the first trimester of pregnancy that the heart is
developing. Due to recent remedial actions at the two sampled
residences, vapor intrusion is not expected to pose current or future
health risks at those residences. However, because of a lack of
sampling data, past, current, and future health risks of possible
short-term TCE exposure at other residences or occupied building
in the neighborhood are not known.
Basis for TCE concentrations in indoor air were found to exceed health-
Conclusion 1 based screening levels at two residences northeast of the site.
Those screening levels are based on several animal and
epidemiological studies that have provided evidence that exposure
to low concentrations of TCE may increase the risk of gestational
or early postnatal development of cardiac malformations. A
mother’s exposure to TCE during the 3 week period of critical
heart formation in the first trimester of pregnancy could result in
an increased risk of a heart defect in the baby. TCE concentrations
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in indoor air at both residences approached a human equivalent
concentration (HEC) associated with potential fetal heart defects
(21 µg/m3).
Soon thereafter, mitigation actions were completed at both
residences to reduce TCE migration into the basements of those
homes. A VI mitigation system was installed at one residence
where TCE was found to be elevated in subslab soil gas. Floor
drain traps were plugged at the other residence where TCE vapors
had seeped into the sewer line.
If the sampling results are representative of TCE concentrations in
indoor air at other homes and occupied buildings in the
neighborhood, TCE may pose past, current, and/or future health
risks to other individuals. Indoor air and subslab soil gas samples
have not been collected at other residences or occupied buildings
in the neighborhood.
Conclusion 2 MDHSS cannot conclude whether chronic (long-term) exposure to
TCE in indoor air at residences or other occupied buildings near
the former Hardesty Federal Complex may harm people’s health, as indoor air sampling has only occurred at two residences
northeast of the site over a limited time period. Potential health
impacts of long-term exposure to TCE include adverse effects on
the immune system and kidneys, which could result from several
months or more of breathing a sufficient dose of TCE in adults and
children, and increased cancer risks from a lifetime of exposure to
TCE.
Basis for TCE concentrations in indoor air at the two sampled residences
Conclusion 2 northeast of the site approached an HEC associated with potential
kidney effects from long-term exposure (30 µg/m3). TCE
concentrations were below an HEC associated with immunological
effects from long-term exposure, although concentrations were
within the range of uncertainty attributed to those effects (1.9 –
190 µg/m3). Long-term concentrations of TCE in indoor air at
those residences are not known, however, as they likely fluctuate
over time. Indoor air and subslab soil gas samples have not been
collected at other residences or occupied buildings in the
neighborhood.
Recommendations MDHSS recommends that concerned parents seek medical advice
about the possibility of heart malformations in their newborn
children if, during pregnancy, TCE concentrations in their indoor
air are found to exceed a level of health concern.
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MDHSS recommends sampling at additional residences and
occupied buildings in the area in a systematic effort to swiftly
determine the extent of TCE vapor migration and intrusion in the
neighborhood and whether TCE is currently posing health risks at
those locations.
MDHSS recommends quickly reducing exposures to TCE at other
residences or occupied buildings, if additional VI sampling
indicates TCE concentrations pose current or future health risks at
those locations.
MDHSS recommends full characterization of groundwater
contamination at the site to determine the extent of migration of
TCE and other potential contaminants from the source zone(s).
MDHSS recommends continued monitoring and maintenance of
implemented controls until the source of VOCs is attenuated or
remediated to below screening levels or until buildings are no
longer susceptible to vapor intrusion.
Next Steps MDHSS will continue to coordinate with GSA, MDNR, or other
agencies in reaching out to the community to educate people on
the adverse health effects of VOC exposures in the hopes that
GSA, MDNR, or other agencies will gain access for VI sampling
in other potentially-impacted homes or occupied buildings in the
community.
MDHSS will coordinate with ATSDR, GSA, MDNR, or other
agencies to notify the community of the findings of this health
consultation and address community health concerns and questions
as requested.
As requested, MDHSS will review and comment on any additional
data from environmental samples collected by GSA, MDNR, or
other agencies as they become available.
FOR MORE If you have concerns about your health or information in this report,
INFORMATION you can contact the Missouri Department of Health and Senior Services at 1-866-628-9891. You may also call ATSDR at 1-800
CDC-INFO and ask for information on the former Hardesty Federal Complex site.
PURPOSE AND HEALTH ISSUES
The Missouri Department of Health and Senior Services (MDHSS), in cooperation with
the Agency for Toxic Substances and Disease Registry (ATSDR), has developed this
health consultation to evaluate the potential public health impacts of exposure to volatile
organic compounds (VOCs) in indoor air at residences and other occupied buildings near
the former Hardesty Federal Complex site in Kansas City, Missouri (MO). This public health evaluation was performed at the request of the Missouri Department of Natural
Resources (MDNR). ATSDR is a federal agency within the United States (U.S.)
Department of Health and Human Services and is authorized by the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) to
conduct public health assessments at hazardous waste sites. The top priority of MDHSS
in performing this evaluation is to provide individuals living or working near the site with
the best information possible to safeguard their health.
SITE DESCRIPTION AND BACKGROUND
The former Hardesty Federal Complex site is located at 607 Hardesty Avenue in Kansas City, MO. The site consists of multiple buildings on approximately 18 acres of
commercial/light industrial property located on the southeast corner of Hardesty Avenue
and East Independence Avenue [Terracon 2013]. Residential, commercial, and light
industrial areas surround the site.
During World War II and start of the Cold War era, the site of the complex served as the
Kansas City Quartermaster Depot, where U.S. Army clothing and equipment were
purchased, stored, and shipped. Military uniforms were also laundered and treated with
an unknown mixture of chemicals to increase their resistance to warfare gases, such as
“mustard gas” [Terracon 2013]. Some chemicals stored on the site at that time (e.g.,
petroleum and cleaning solvents) were stored in underground storage tanks, which over
time began to leak into the soil and groundwater. Chemicals were also reportedly stored
in tanks housed in concrete pits.
In 1960, ownership of the site was transferred to the U.S. General Services
Administration (GSA), who recently sold much of the site to the Hardesty Renaissance
Economic Development Corporation. Although the site is now under private ownership,
GSA, in coordination with MDNR, has maintained oversight of the environmental
investigation of the site and cleanup of contaminants related to past activities at the site.
In a preliminary assessment of environmental contamination at the site conducted in
2002, chlorinated VOCs were detected in soil and shallow groundwater up to the
northeast boundary of the site [Terracon 2013]. Targeted chlorinated compounds
included tetrachloroethylene (PCE), tetrachloroethane (PCA), trichloroethane (TCA),
trichloroethylene (TCE), and dichloroethene (DCE). The sampling results indicated that
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chlorinated VOCs released into soil and groundwater near the former clothing renovation
building had traveled at least to the boundary of the site in the direction of groundwater
flow to the east-northeast [Terracon 2013]. In 2003, following the onsite assessment,
GSA, in coordination with MDNR, performed an initial investigation of offsite
contaminant migration. In the offsite sampling performed in a residential area northeast
of the site, TCE was found to be a contaminant in deep groundwater [Terracon 2013].
Residences surrounding the site are connected to the public water supplied by the Kansas
City Missouri Water Supply Department, which obtains water from the Missouri River
[Terracon 2013]. Therefore, residents are not at risk of exposure to TCE from the site
through the public drinking water supply.
In 2010-2011, in an expanded offsite investigation, TCE was detected in shallow and
deep groundwater collected from some monitoring wells northeast of the site. TCE
concentrations were as high as 7.6 µg/L in shallow groundwater and 274 µg/L in deep
groundwater collected from offsite wells [Terracon 2013]. Although TCE concentrations
at several sampling locations were below laboratory detection limits, and although
detected TCE concentrations were higher in deep groundwater than in shallow
groundwater, those limited findings indicated a potential for offsite TCE vapor intrusion
(VI). In a VI exposure pathway, VOCs volatilize from soil and groundwater and travel
into homes and other buildings, where they may accumulate to levels of potential health
concern.
In 2014, GSA, in coordination with MDNR, conducted VI sampling at two residences in
the neighborhood northeast of the site. The results of that initial offsite VI investigation
are discussed in this health consultation. Since that time, GSA and MDNR have sought
to expand off-site VI sampling to include additional properties, particularly residences
northeast of the site but also properties east and southeast of the site that recent
environmental investigations indicate could also be at risk of vapor intrusion.
Demographics
According to the 2010 U.S. Census, 22,110 people live within a one mile radius of the
former Hardesty Federal Complex. Within that radius, approximately 45% are white, 13% are African American, 5% are Asian, and 37% are other races. Approximately 45%
of the population identified themselves as Hispanic or Latino. Map 1 shows detailed
demographic information on the area surrounding the site.
As shown in Appendix A (Map A-1), populations surrounding the site fall within the top
25% of the 2010 social vulnerability index. The social vulnerability index is used to
identify populations that may be especially vulnerable to developing adverse health
effects from the release of chemicals from hazardous waste sites. Increased vulnerability
may be due to factors such as cultural or language barriers that may limit a person’s
access to the benefits of public health outreach efforts. It is measured by socioeconomic
status, family composition, race/ethnicity/language, and housing/transportation access.
According to the 2010 U.S. Census, 30.2% of the population living in Zip Code 64123,
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including the neighborhood northeast of the site, speak languages other than English at
home [U.S. Census Bureau 2010].
As shown in Appendix A (Map A-2), approximately 22% of the population living within
a 1-mile radius of the site are females aged 15-44 years. It is especially important to
prevent TCE exposure in women of child-bearing age, because of the potential
susceptibility of a fetus to adverse health effects from short-term TCE exposures.
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Map 1. Demographic statistics within a 1 mile radius of the former HardestyFederal Complex site.
DISCUSSION
Vapor Intrusion Pathway
If VOCs are released into the soil and groundwater at a site, they can travel offsite as a
groundwater and/or soil gas contaminant [EPA 2015; ITRC 2007]. VOCs in soil gas that
comes in close proximity to residences and commercial buildings may travel through
cracks in the foundation or other conduits and accumulate in indoor air. If VOCs
accumulate in indoor air to levels of potential health concern, breathing those VOCs even
for short periods of time could pose adverse health risks.
Rates of vapor intrusion into indoor air can vary significantly, depending on the site
geology, building construction, and the presence of cracks in building foundations [EPA
2015; ITRC 2007]. VI investigations are complicated by the potential for VOCs to travel
by various pathways and by the tendency for the rates of vapor intrusion to differ even in
neighboring homes. Identification of complete VI pathways of exposure generally
requires a “multiple lines of evidence” approach, involving collection of groundwater,
soil gas, indoor air, subslab soil gas, and/or crawl space air samples. Household or
workplace chemicals containing VOCs can also contribute to concentrations measured in
indoor air. The VI pathway is considered to be complete if VOC concentrations in indoor
air are attributed to VOCs in soil gas or shallow groundwater.
Residential Sampling Results
From August to October 2014, GSA and MDNR in consultation with MDHSS conducted
a VI investigation at residences near the former Hardesty Federal Complex. Indoor air and subslab soil gas samples were collected at two homes located northeast of the site.
Table 1 shows a summary of the results of that investigation. At both residences, TCE
was detected in indoor air. Other chlorinated VOCs were not detected in either indoor air
or subslab soil gas samples.
At one residence, TCE in indoor air was attributed to intrusion of TCE vapors into the
sewer line. In the initial round of sampling, TCE in indoor air at that residence exceeded
health-based screening levels, while TCE in subslab soil gas was relatively low. The
source of TCE in the indoor air at that residence was not evident until traps in two floor
drains were plugged to prevent the transport of vapors from the sewer line into the
basement of the house. In a second round of VI sampling, after floor drains were
plugged, TCE concentrations in the basement fell below health-based screening levels.
At the other residence, TCE in indoor air was attributed to the migration of subsurface
soil gas vapors through the basement foundation. TCE concentrations in indoor air at
that residence were initially below health-based screening levels. However, TCE in
subslab soil gas concentrations exceeded a screening level by approximately 10-times, indicating a potential for vapor intrusion at that residence. In a second round of VI
sampling, TCE concentrations in indoor air were found to exceed health-based screening
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levels, apparently as a result of the “stack effect” (i.e., increased rates of vapor intrusion
that accompanies a change in indoor air pressure when heating systems are in use). A VI
mitigation system was installed at that residence to reduce/prevent future vapor intrusion
of subslab soil gas into the indoor air.
Table 1. Trichloroethylene in Residential Air and Soil Gas Samples
Former Hardesty Federal Complex Site, Kansas City, Missouri
August - October 2014
Location
Sample Typea
(9 samples)
Range of TCE
Concentrationsb
(µg/m3)
Health-Based
Screening
Levelsc
(µg/m3)
Exceeded
Screening Level?
Residence
1
Indoor Air (2) 2.1 – 11.0 2.1 (noncancer)
0.24 (cancer) Yes
Subslab Soil Gas
(1) 0.8 70 (noncancer) No
Residence
2
Indoor Air (4) 0.1 – 7.3 2.1 (noncancer)
0.24 (cancer) Yes
Subslab Soil Gas
(2) 680 – 1,600 70 (noncancer) Yes
aNumber of samples shown in parentheses collected prior to VI mitigation bConcentrations detected prior to VI mitigation. cIndoor air screening levels are ATSDR’s minimum risk levels (MRLs) for screening of noncancer health
risks from intermediate and chronic exposures to TCE and ATSDR’s cancer risk evaluation guide (CREG)
for screening of cancer risks of lifetime exposure to TCE. The subslab screening level is derived from the noncancer indoor air screening level using EPA’s default attenuation factor of 0.03 [EPA 2015].
Additional Sampling in the Surrounding Community
Residences and other buildings northeast, east, and southeast of the site are considered to
be at potential risk of vapor intrusion. GSA, MDNR, and other agencies have made
multiple attempts to notify neighbors of the need for additional VI investigations,
including attempts by mail and door-to-door visits. However, GSA and MDNR have yet
to gain access to additional properties for VI sampling. MDHSS will assist other
agencies, as requested, to reach out to the community and communicate the findings of
this health consultation to encourage their participation in the VI investigations.
In addition to participating in door-to-door visits, MDHSS, MDNR, the Kansas City
Health Department, and other agencies have attended public availability sessions hosted
by GSA to discuss planned sampling activities and potential health concerns with local
residents. Public availability sessions were held on 6/20/13, 12/5/13, 10/29/14, and
11/17/15 at the North-East Branch of the Kansas City Public Library. Spanish and
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Vietnamese interpreters have been available to assist members of the public who speak
those languages commonly used in the neighborhood. GSA also has developed
educational materials including newsletters and site update fact sheets in various
languages, including Spanish, Somali, and Vietnamese.
PUBLIC HEALTH IMPLICATIONS
The health risks of exposure to environmental contaminants are initially evaluated by
comparison of the concentrations of those contaminants to health-based guidelines
established by ATSDR, EPA, and other agencies. Screening levels developed by
ATSDR include minimal risk levels (MRLs), which are estimates of acute (< 2 weeks),
intermediate (2 weeks to 1 year) exposure not likely to result in
adverse, non-cancer health effects. Screening levels developed by other agencies include
EPA’s reference concentrations (RfCs), which are inhalation exposure levels unlikely to
cause non-cancer effects in humans over a lifetime. ATSDR’s cancer risk evaluation
guides (CREGs) are used in assessing the risks of exposure to known or potential
carcinogens.
Contaminant concentrations that exceed screening level values do not necessarily pose
health risks. Several factors determine whether individuals will develop adverse health
effects, including age, health and nutritional status, and the amount and length of time of
exposure. In this section, the potential health impacts of exposure to TCE in indoor air at
the sampled residences northeast of the Hardesty site are further evaluated.
Non-Cancer Effects
In 2011, EPA developed a noncancer screening level for TCE from studies showing development of cardiac malformations in rats over approximately three weeks of
gestational exposure to TCE, and immunological effects in mice after 30 weeks of
exposure to TCE [EPA 2011]. In its review of those studies, EPA derived TCE
concentrations in air that might be expected to have the same effects in humans. Human
equivalent concentrations (HECs) are 21 µg/m3 TCE for short-term exposures potentially
associated with cardiac malformations and 190 µg/m3 TCE for chronic exposures potentially associated with immunological effects [EPA 2011].
Based on EPA’s evaluation of those studies, ATSDR established an MRL for chronic (>1
year) inhalation exposure to TCE (2.1 µg/m3) [ATSDR 2013]. Because of TCE’s potential effects on fetal heart development with short-term exposures, ATSDR has also
applied that screening level to intermediate (2 weeks to
most sensitive targets of TCE exposure appear to be the kidneys and immune system
[EPA 2011]. Immunological studies, including epidemiological studies, indicate that
chronic exposure to a sufficient dose of TCE may increase the risk of development of
autoimmune diseases and hypersensitivity skin disorder, as well as possible suppression
of the immune system [Chiu 2012]. These include inflammatory diseases and
scleroderma, a hardening of the skin. There is also substantial evidence that, at sufficient
dose and exposure duration, TCE is toxic to the nervous system, kidney, liver, and male
reproductive system and is associated with other developmental effects [ATSDR 2013].
At both sampled residences northeast of the Hardesty site, maximum TCE concentrations
in indoor air prior to VI mitigation (7.3 µg/m3 and 11 µg/m3) approached the estimated
HEC for fetal cardiac malformations (21 µg/m3). As TCE concentrations in indoor air
likely fluctuate, past TCE concentrations in indoor air could have exceeded the HEC. As
a result, DHSS concludes that breathing TCE in indoor air at those residences may have
increased the risks of fetal heart malformations. A mother’s exposure to TCE during the
three week period of critical heart formation in the first trimester of pregnancy could
result in an increased risk of a heart defect in the baby.
At both sampled residences, maximum TCE concentrations fell within a range of
uncertainty applied to the HEC for immunological effects (i.e., from 1.9 µg/m3 to 190
µg/m3). In addition, maximum TCE concentrations approached the concentration
associated with adverse kidney effects (30 µg/m3) that EPA used to support establishment
its screening level [EPA 2011]. As TCE concentrations in indoor air likely fluctuated,
long-term TCE concentrations in indoor air could have approached or exceeded HECs.
Potential long-term exposure concerns include adverse effects on the kidneys and
immune system in adults and children. Since indoor air sampling only occurred over a
limited time period, MDHSS cannot draw more definite conclusions about potential
health concerns due to chronic (long-term) exposures.
Estimated Cancer Risks
Cancer is very common. The American Cancer Society estimates that nearly half of men
and slightly more than a third of women in the United States will develop some form of
cancer in their lifetimes [Siegel et al 2016]. Thus, estimates of cancer risk from chemical
exposure are referred to as “increased risk” estimates. There are multiple types of cancer
that have different risk factors and affect different organs.
EPA classifies TCE as carcinogenic to humans. The National Toxicology Program
(NTP) has determined that TCE is reasonably anticipated to be a human carcinogen,
based on evidence from animal studies and limited evidence from human studies [NTP
2011]. Long-term TCE exposure is associated with liver and kidney cancers and non-
Hodgkins lymphoma by multiple routes, including inhalation exposure [EPA 2011;
ATSDR 2013]. Because kidney cancer may develop by a mutagenic mode of action from
exposure to TCE, children may be especially susceptible to TCE’s carcinogenic effects.
It is possible that increased cancer risks from breathing TCE could be somewhat higher if
exposures occur during childhood [EPA 2011; ATSDR 2013].
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In this health consultation, cancer risk was estimated from the highest TCE concentration
detected in residential indoor air prior to VI mitigation, using EPA’s Age-Dependent
Adjustment Factors (ADAFs) to account for increased early-life susceptibility to kidney
cancer [EPA 2011]. Shown in Table 2 is an estimate of increased cancer risk that
assumes residents might continuously breathe TCE in indoor air over a lifetime (see
calculations in Appendix B). The estimated value represents, at most, 5 additional
cancer cases in a population of 100,000 people exposed to the same TCE concentration
over a lifetime.
Table 2. Potential Increase in Cancer Rates from Lifetime Exposure to
Trichloroethylene in Sampled Residences
Former Hardesty Federal Complex Site, Kansas City, Missouri
Maximum Cancer Risk Valuea Potential Increase in
Cancer Rates
TCE 5.2 × 10-5 5 additional cases per
100,000 people aBased on the maximum concentration detected in indoor air prior to VI mitigation
The value in Table 2 is a rough estimate based on limited sampling results. Because it is
likely that residents are actually breathing the indoor air in their homes for less than 24
hours/7-days per week over a lifetime, increased cancer risks from breathing TCE could
be lower than the estimated value. Also, because long-term exposure levels in the
homes and occupied buildings surrounding the site are not known, increased cancer risks
from breathing TCE could be significantly higher or lower than the estimated value.
Without long-term data, MDHSS cannot draw more definite conclusions about cancer
risks in the populations surrounding the former Hardesty Federal Complex site.
LIMITATIONS
MDHSS has identified the following limitations to assessing the public health risks of
vapor intrusion in homes and other occupied buildings in the neighborhood surrounding
the Hardesty property:
• The VI investigation has so far been limited to two homes located northeast of the Hardesty site. However, groundwater sampling, in addition to the results of this
VI investigation, suggest that vapor intrusion may be occurring in many homes
and occupied buildings in the neighborhood surrounding the site. MDNR and
GSA have not been able to gain access to other homes or occupied buildings for
VI sampling.
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• Because long-term average concentrations of TCE in indoor air are not known, MDHSS is unable to draw definite conclusions about the health risks of long-term
exposure to TCE in indoor air.
CONCLUSIONS
1. In the past, breathing TCE in indoor air may have posed increased health risks in
two residences northeast of the former Hardesty Federal Complex site. Of particular
concern are the increased risks of fetal heart malformations from TCE exposure during
the weeks in the first trimester of pregnancy that the heart is developing. Due to recent
remedial actions at the two sampled residences, vapor intrusion is not expected to pose
current or future health risks at those residences. However, because of a lack of
environmental sampling data, past, current, and future health risks of possible short-term
TCE exposure at other residences or occupied building in the neighborhood are not
known.
2. MDHSS cannot conclude whether chronic (long-term) exposure to TCE in indoor
air at residences or other occupied buildings near the former Hardesty Federal Complex
may harm people’s health, as indoor air sampling has only occurred at two residences
northeast of the site over a limited time period. Potential health impacts of long-term
exposure to TCE include adverse effects on the immune system and kidneys, which could
result from several months or more of breathing a sufficient dose of TCE in adults and
children, and increased cancer risks from a lifetime of exposure to TCE.
RECOMMENDATIONS
1. MDHSS recommends that concerned parents seek medical advice about the
possibility of heart malformations in their newborn children if, during pregnancy, TCE
concentrations in their indoor air are found to exceed a level of health concern.
2. MDHSS recommends sampling at additional residences and occupied buildings in
the area in a systematic effort to swiftly determine the extent of TCE vapor migration and
intrusion in the neighborhood and whether TCE is currently posing health risks at those
locations.
3. MDHSS recommends quickly reducing exposures to TCE at other residences or
occupied buildings, if additional VI sampling indicates TCE concentrations pose current
or future health risks at those locations.
4. MDHSS recommends full characterization of groundwater contamination at the
site to determine the extent of migration of TCE and other potential contaminants from
the source zone(s).
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5. MDHSS recommends continued monitoring and maintenance of implemented
controls until the source of VOCs is attenuated or remediated to below screening levels or
until buildings are no longer susceptible to vapor intrusion.
PUBLIC HEALTH ACTION PLAN
The Public Health Action Plan (PHAP) for the former Hardesty Federal Complex site contains a description of future actions by MDHSS, ATSDR, and other stakeholders.
The purpose of the PHAP is to ensure that this public health consultation not only
identifies public health hazards, but provides an action plan to prevent adverse human
health effects resulting from past, present, and future exposures to hazardous substances
at or near the site. Below is a list of commitments of public health actions by MDHSS:
1. MDHSS will continue to coordinate with GSA, MDNR, or other agencies in
reaching out to the community to educate people on the adverse health effects
of VOC exposures in the hopes that GSA, MDNR, or other agencies will gain
access for VI sampling in other potentially-impacted homes or occupied
buildings in the community.
2. MDHSS will coordinate with ATSDR, GSA, MDNR, or other agencies to
notify the community of the findings of this health consultation and address
community health concerns and questions as requested.
3. As requested, MDHSS will review and comment on additional data from
environmental samples collected by GSA, MDNR, or other agencies as they
become available.
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REPORT PREPARATION
This Health Consultation for the former Hardesty Federal Complex site was prepared by the Missouri Department of Health and Senior Services under a cooperative agreement
with ATSDR. It is in accordance with the approved agency methods, policies, and
procedures existing at the date of publication. Editorial review was completed by the
cooperative agreement partner. ATSDR has reviewed this document and concurs with its
findings based on the information presented.
Authors
Elizabeth Semkiw
Environmental Specialist
Bureau of Environmental Epidemiology
Section for Environmental Public Health
Missouri Department of Health and Senior Services
State Reviewers
Dennis Wambuguh
Health and Risk Assessment Unit Chief
Bureau of Environmental Epidemiology
Section for Environmental Public Health
Missouri Department of Health and Senior Services
Jonathan Garoutte
Chief of the Bureau of Environmental Epidemiology
Section for Environmental Public Health
Missouri Department of Health and Senior Services
Reviewers
Trent LeCoultre
Technical Project Officer
Division of Community Health Investigations
Agency for Toxic Substances and Disease Registry
Kai Elgethun
Western Branch Associate Director for Science
Division of Community Health Investigations
Agency for Toxic Substances and Disease Registry
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REFERENCES
[ATSDR] Agency for Toxic Substances and Disease Registry. 2013.
Addendum to the Toxicological Profile for Trichloroethylene (TCE). Atlanta,
GA: U.S. Department of Health and Human Services, Public Health Service.
Available online at http://www.atsdr.cdc.gov/toxprofiles/tce_addendum.pdf
Chiu, W.A. et al. 2012. Human Health Effects of Trichloroethylene: Key Findings and
Scientific Issues. Environmental Health Perspectives. National Institute of
Environmental Health Sciences, U.S. Department of Health and Human Services.
[EPA] U.S. Environmental Protection Agency. 2011. Toxicological Review of
Trichloroethylene: In Support of Summary Information on the Integrated Risk
Information System (IRIS). Environmental Protection Agency. EPA/635/R-09/011F.
[EPA] U. S. Environmental Protection Agency. 2015. OWSER Technical Guide for
Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface Vapor Sources
to Indoor Air. Office of Solid Waste and Emergency Response. OWSER Publication
No.: 9200.2-154.
[ITRC] Interstate Technology & Regulatory Council. 2007. Vapor Intrusion Pathway: A
Practical Guideline. VI-1. Washington, D.C.: Interstate Technology & Regulatory
Council, Vapor Intrusion Team. Available online at: www.itrcweb.org
[NTP] National Toxicology Program. 2011. Report on carcinogens, 12th edition.
Research Triangle Park, NC: U.S. Department of Health and Human Services, Public
Health Service, National Toxicology Program. 499 pp.
Siegel RL et al. 2016. Cancer statistics, 2016. CA Cancer J. Clin. Available online at:
www.cancer.org
Terracon Consultants, Inc. 2013. Remedial Investigation/Feasibility Study Work Plan,
Hardesty Federal Complex. Prepared for the United States General Services
Administration, Kansas City, Missouri. March 2013.
U. S. Census Bureau. 2010. American FactFinder, Community Facts, 2010 Census.
Available at: http://www.census.gov/
18
http:http://www.census.govhttp:www.cancer.orghttp:www.itrcweb.orghttp://www.atsdr.cdc.gov/toxprofiles/tce_addendum.pdf
19
APPENDIX A: MAPS
Map A-1. Vulnerable populations living near the former Hardesty Federal
Complex site.
20
Map A-2. Sensitive populations living near the former Hardesty Federal Complex
site.
21
22
APPENDIX B: ESTIMATED CANCER RISKS
Calculation of Estimated Increased Cancer Risks from Exposure to TCE
former Hardesty Federal Complex site.
Increases in cancer risk from the inhalation of TCE in indoor air at two sampled
residences were estimated assuming individuals have been exposed to the maximum TCE
concentration detected in indoor air prior to VI mitigation.
Calculations are based on EPA’s inhalation unit risk factors (IUFs) and age dependent
adjustment factors (ADAFs). Table B-1 is the calculation spreadsheet for estimating the
increased cancer risk from lifetime exposure to TCE, which takes into consideration
higher early-life susceptibility to kidney cancer.
Estimated Cancer Risks of Inhalation of TCE:
Cancer Risk = Air Concentration × IUF × ADAFs
Cancer Risk 1 µg/m3(high) = 1 × (4.1×10-6 (µg/m3)-1) × ADAFs
Estimated Cancer Risk = 5.2 × 10-5
Approximate Increase in Cancer Risk: 5 cases per 100 thousand people
23
Table B-1. Maximum Age-Specific Increased Cancer Risks from Exposure to TCE in
Indoor Air Age Exposure
Duration
(adjusted)a
TCE
conc. b
(µg/m3)
Kidney
cancer
unit risk
factorc
ADAFd Kidney
cancer
partial riske
NHL &
Liver
cancer unit
risk factorf
NHL &
Liver
cancer
Partial
riskg
Total
Partial
Riskh
Birth
